/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | foam-extend: Open Source CFD
   \\    /   O peration     | Version:     4.1
    \\  /    A nd           | Web:         http://www.foam-extend.org
     \\/     M anipulation  | For copyright notice see file Copyright
-------------------------------------------------------------------------------
License
	This file is part of foam-extend.

	foam-extend is free software: you can redistribute it and/or modify it
	under the terms of the GNU General Public License as published by the
	Free Software Foundation, either version 3 of the License, or (at your
	option) any later version.

	foam-extend is distributed in the hope that it will be useful, but
	WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
	General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with foam-extend.  If not, see <http://www.gnu.org/licenses/>.

\*---------------------------------------------------------------------------*/

#include "OFFsurfaceFormat.H"
#include "clock.H"
#include "IFstream.H"
#include "IStringStream.H"
#include "Ostream.H"
#include "OFstream.H"

// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //

template<class Face>
Foam::fileFormats::OFFsurfaceFormat<Face>::OFFsurfaceFormat
(
	const fileName& filename
)
{
	read(filename);
}


// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //

template<class Face>
bool Foam::fileFormats::OFFsurfaceFormat<Face>::read
(
	const fileName& filename
)
{
	const bool mustTriangulate = this->isTri();
	this->clear();

	IFstream is(filename);
	if (!is.good())
	{
		FatalErrorIn
		(
			"fileFormats::OFFsurfaceFormat::read(const fileName&)"
		)
			<< "Cannot read file " << filename
			<< exit(FatalError);
	}

	// Read header
	string hdr = this->getLineNoComment(is);
	if (hdr != "OFF")
	{
		FatalErrorIn
		(
			"fileFormats::OFFsurfaceFormat::read(const fileName&)"
		)
			<< "OFF file " << filename << " does not start with 'OFF'"
			<< exit(FatalError);
	}


	// get dimensions
	label nPoints, nElems, nEdges;

	string line = this->getLineNoComment(is);
	{
		IStringStream lineStream(line);
		lineStream >> nPoints >> nElems >> nEdges;
	}

	// Read points
	pointField pointLst(nPoints);
	forAll(pointLst, pointI)
	{
		scalar x, y, z;
		line = this->getLineNoComment(is);
		{
			IStringStream lineStream(line);
			lineStream >> x >> y >> z;
		}
		pointLst[pointI] = point(x, y, z);
	}

	// Read faces - ignore optional zone information
	// use a DynamicList for possible on-the-fly triangulation
	DynamicList<Face>  dynFaces(nElems);

	for (label faceI = 0; faceI < nElems; ++faceI)
	{
		line = this->getLineNoComment(is);

		{
			IStringStream lineStream(line);

			label nVerts;
			lineStream >> nVerts;

			labelList verts(nVerts);

			forAll(verts, vertI)
			{
				lineStream >> verts[vertI];
			}

			UList<label>& f = static_cast<UList<label>&>(verts);

			if (mustTriangulate && f.size() > 3)
			{
				// simple face triangulation about f[0]
				// cannot use face::triangulation (points may be incomplete)
				for (label fp1 = 1; fp1 < f.size() - 1; fp1++)
				{
					label fp2 = f.fcIndex(fp1);

					dynFaces.append(triFace(f[0], f[fp1], f[fp2]));
				}
			}
			else
			{
				dynFaces.append(Face(f));
			}
		}
	}

	// transfer to normal lists, no zone information
	this->reset(pointLst.xfer(), dynFaces.xfer(), Xfer<surfZoneList>());

	return true;
}


template<class Face>
void Foam::fileFormats::OFFsurfaceFormat<Face>::write
(
	const fileName& filename,
	const MeshedSurfaceProxy<Face>& surf
)
{
	const pointField& pointLst = surf.points();
	const List<Face>&  faceLst = surf.faces();
	const labelList& faceMap = surf.faceMap();
	const List<surfZone>& zoneLst = surf.surfZones();

	OFstream os(filename);
	if (!os.good())
	{
		FatalErrorIn
		(
			"fileFormats::OFFsurfaceFormat::write"
			"(const fileName&, const MeshedSurfaceProxy<Face>&)"
		)
			<< "Cannot open file for writing " << filename
			<< exit(FatalError);
	}

	// Write header
	os  << "OFF" << endl
		<< "# Geomview OFF file written " << clock::dateTime().c_str() << nl
		<< nl
		<< "# points : " << pointLst.size() << nl
		<< "# faces  : " << faceLst.size() << nl
		<< "# zones  : " << zoneLst.size() << nl;

	// Print zone names as comment
	forAll(zoneLst, zoneI)
	{
		os  << "#   " << zoneI << "  " << zoneLst[zoneI].name()
			<< "  (nFaces: " << zoneLst[zoneI].size() << ")" << nl;
	}

	os  << nl
		<< "# nPoints  nFaces  nEdges" << nl
		<< pointLst.size() << ' ' << faceLst.size() << ' ' << 0 << nl
		<< nl
		<< "# <points count=\"" << pointLst.size() << "\">" << endl;

	// Write vertex coords
	forAll(pointLst, ptI)
	{
		os  << pointLst[ptI].x() << ' '
			<< pointLst[ptI].y() << ' '
			<< pointLst[ptI].z() << " #" << ptI << endl;
	}

	os  << "# </points>" << nl
		<< nl
		<< "# <faces count=\"" << faceLst.size() << "\">" << endl;

	label faceIndex = 0;
	forAll(zoneLst, zoneI)
	{
		os << "# <zone name=\"" << zoneLst[zoneI].name() << "\">" << endl;

		if (surf.useFaceMap())
		{
			forAll(zoneLst[zoneI], localFaceI)
			{
				const Face& f = faceLst[faceMap[faceIndex++]];

				os << f.size();
				forAll(f, fp)
				{
					os << ' ' << f[fp];
				}

				// add optional zone information
				os << ' ' << zoneI << endl;
			}
		}
		else
		{
			forAll(zoneLst[zoneI], localFaceI)
			{
				const Face& f = faceLst[faceIndex++];

				os << f.size();
				forAll(f, fp)
				{
					os << ' ' << f[fp];
				}

				// add optional zone information
				os << ' ' << zoneI << endl;
			}
		}
		os << "# </zone>" << endl;
	}
	os << "# </faces>" << endl;
}


// ************************************************************************* //
